Table 2-9. Completion Network Jumpers - National Instruments SCXI-1121 User Manual

Chapter 2 Configuration and Installation
Note When using the half-bridge completion network with a quarter-bridge setup, you
must use an extra resistor to complete the bridge. Place this resistor on the terminal block
between the positive input channel and the negative excitation output.
Channel
0
1
SCXI-1121 User Manual
Using the Internal Half-Bridge Completion
Your SCXI-1121 includes half-bridge completion for half-bridge and
quarter-bridge setups. The completion network consists of two
4.5 k ± 0.05% ratio tolerance resistors with a temperature coefficient of
5 ppm/°C. These resistors are connected in series. To enable the network,
you must set two jumpers for each input/excitation channel pair.
When the completion network is enabled, you cannot access the negative
input of the amplifier, which preserves the overvoltage protection of the
channel. Table 2-9 shows how to enable and disable the completion
network.

Table 2-9. Completion Network Jumpers

Jumpers
W1 and W2
W17 and W18
Enable Completion
• •
W2
• •
A B
W1
1 2 3
• •
W18
• •
A B
W17
1 2 3
2-12
Disable Network
(Factory Setting)
• •
W2
• •
A B
W1
1 2 3
• •
W18
• •
A B
W17
1 2 3
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